return 0;
 }
 
+static inline struct intel_iommu *dev_to_intel_iommu(struct device *dev)
+{
+       return container_of(dev, struct intel_iommu, iommu.dev);
+}
+
 static ssize_t intel_iommu_show_version(struct device *dev,
                                        struct device_attribute *attr,
                                        char *buf)
 {
-       struct intel_iommu *iommu = dev_get_drvdata(dev);
+       struct intel_iommu *iommu = dev_to_intel_iommu(dev);
        u32 ver = readl(iommu->reg + DMAR_VER_REG);
        return sprintf(buf, "%d:%d\n",
                       DMAR_VER_MAJOR(ver), DMAR_VER_MINOR(ver));
                                        struct device_attribute *attr,
                                        char *buf)
 {
-       struct intel_iommu *iommu = dev_get_drvdata(dev);
+       struct intel_iommu *iommu = dev_to_intel_iommu(dev);
        return sprintf(buf, "%llx\n", iommu->reg_phys);
 }
 static DEVICE_ATTR(address, S_IRUGO, intel_iommu_show_address, NULL);
                                    struct device_attribute *attr,
                                    char *buf)
 {
-       struct intel_iommu *iommu = dev_get_drvdata(dev);
+       struct intel_iommu *iommu = dev_to_intel_iommu(dev);
        return sprintf(buf, "%llx\n", iommu->cap);
 }
 static DEVICE_ATTR(cap, S_IRUGO, intel_iommu_show_cap, NULL);
                                    struct device_attribute *attr,
                                    char *buf)
 {
-       struct intel_iommu *iommu = dev_get_drvdata(dev);
+       struct intel_iommu *iommu = dev_to_intel_iommu(dev);
        return sprintf(buf, "%llx\n", iommu->ecap);
 }
 static DEVICE_ATTR(ecap, S_IRUGO, intel_iommu_show_ecap, NULL);
                                      struct device_attribute *attr,
                                      char *buf)
 {
-       struct intel_iommu *iommu = dev_get_drvdata(dev);
+       struct intel_iommu *iommu = dev_to_intel_iommu(dev);
        return sprintf(buf, "%ld\n", cap_ndoms(iommu->cap));
 }
 static DEVICE_ATTR(domains_supported, S_IRUGO, intel_iommu_show_ndoms, NULL);
                                           struct device_attribute *attr,
                                           char *buf)
 {
-       struct intel_iommu *iommu = dev_get_drvdata(dev);
+       struct intel_iommu *iommu = dev_to_intel_iommu(dev);
        return sprintf(buf, "%d\n", bitmap_weight(iommu->domain_ids,
                                                  cap_ndoms(iommu->cap)));
 }